Impact of Co-Ni substitution on the structural and dielectric properties of calcium copper titanate

CCTO ceramics are known for their high dielectric constant and low loss, making them potential candidates for use in various electronic and energy storage applications. The dielectric properties of CCTO ceramics can be tuned by doping of various elements. In addition to the dielectric properties, Co-Ni substitution has also been found to affect other properties of CCTO ceramics, such as the thermal and electrical conductivity. Therefore, Co-Ni substitution can be a useful strategy for tailoring the properties of CCTO ceramics for specific applications. In this research work, the sol-gel auto-combustion technique is used for the synthesis of Co-Ni-substituted calcium copper titanate, Ca(1-x)Co(x)Cu3Ti(4-y)Ni(y)O22 (x = 0.0/y = 0.0, x = 0.1/y = 0.3 and x = 0.2/y = 0.4). X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and impedance analyzer have all been used to examine the structural and dielectric properties of synthesized samples. X-ray diffraction study shows the presence of crystalline structure of calcium copper titanate. The presence of peaks at 422 cm(-1), 503 cm(-1), and 506 cm(-1) in FTIR spectra also confirms the presence of CCTO. The Debye-type relaxation technique and Maxwell-Wagner model describe dielectric characteristics. The grain boundary resistance (R-gb) significantly contributes to the dielectric properties of synthesized calcium copper titanate as seen by the Cole-Cole plot.